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    <meta charset="UTF-8">
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    <title>Document</title>
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<body>
    <script>
        //数组forEach方法，理解为循环，迭代的意思
        //直接上方法
        let arr = [1,2,3,4]
        arr.forEach((item,i)=>{
            console.log('第'+i+'个:'+item)
        })
    </script>
</body>
</html>